Re:fin rot

Pete Giwojna

Dear Lee:

I’m sorry dear that you have a pony that may be developing fin rot, but I would be happy to recommend some treatment options for you to consider.

The most effective medications I know for treating fin rot are combo drugs that include sulfa antibiotics together with trimethoprim (TMP), and I recommend a two-pronged treatment regimen as follows:

First Step: administer a formalin bath to the affected seahorse and then transfer it to your hospital tank for further treatment.

Second Step: administer a complete regimen of either TMP-Sulfa or 4 Sulfa TMP in your hospital tank.

However, Lee, you will probably need to obtain the sulfa/trimethoprim combination drugs and the formalin from an online source such as National Fish Pharmaceuticals, and it would not be healthy for your seahorse to wait for those medications to be delivered. So, unless you have the formalin and TMP-Sulfa or 4 Sulfa TMP on hand right now, that I would recommend that you treat the affected seahorse in your hospital tank using Instant Ocean Lifeguard. The active ingredient in the Lifeguard is not an antibiotic, but it is effective against a wide range of ailments, including fin rot and it has the added virtue that it is inexpensive and readily available at any well-stocked pet shop or fish store. In other words, you should be able to obtain the Instant Ocean Lifeguard locally so that you can begin treatment right away.

Begin treating with the Instant Ocean Lifeguard as soon as possible, and that should at least buy you enough time to obtain the other medications I mentioned. While you are treating the seahorse with the lifeguard, go ahead and obtain the formalin and either TMP-Sulfa or else 4 Sulfa TMP from National Fish Pharmaceuticals so that you have them on hand for follow-up treatment, if necessary.

In the meantime, I will be happy to provide you with more information about fin rot, its causes, and the treatments that I have found to be the most effective for seahorses.

Fin Rot

This condition usually begins as a white line along the margin of the fin and, as the infection progresses and the membrane of the fin gets eaten away, the rigid fin rays become exposed and the fin frays as a result. As long as you detect the condition early and begin treatment before the fin is eroded away all the way to the body, allowing the infection to invade the underlying musculature, the chances for a complete recovery are very good and the damage to the fin will quickly regenerate itself once the infection is eliminated. For example, this is how I described fin rot in my old "Step-By-Step Book about Seahorses:"

<open quote>
Fin Rot in Seahorses

"Fin rot is another problem that sometimes afflicts seahorses in captivity. When this happens, the alert aquarist will notice that the fins of the seahorse are beginning to look frayed and ragged for no apparent reason. This damage is most obvious in the dorsal fin, which is almost always the first to be attacked. In its early stages, this disease is evident as a fine white line along the edge of the fin, which gradually advances towards the base of the fin until the fin rays become exposed, protruding like the ribs of a tattered umbrella. If the bacterial rot is left untreated, the entire fin will be destroyed and the body tissues of the seahorse will become infected, at which point it can no longer be saved. Early detection and treatment is crucial for curing fin rot. At the first sign of fin rot, Mildred Bellamy recommends submerging the infected seahorse in a numeral 1:4000 solution of copper sulfate for one to two minutes. As she cautions, fishes undergoing this chemical baths should be watched closely and removed at the slightest sign of distress regardless of how much time has elapsed. A second bath should be administered in exactly the same manner 24 hours later. Along with these chemical dips, she also recommends that the infected fins be swabbed with a good bacteriocidal agent, such as hydrogen peroxide or merbromin (brand name Betadine), three or four times daily for a period of five to seven days. It may also be helpful to gradually lower the specific gravity of the aquarium water to about 1.020 during treatment, since fin rot is sometimes associated with high salinity.

"Providing the fin rot is detected early, or is only a mild infection, seahorses usually recover completely following this regimen of treatment, and the damaged fin will be fully regenerated. Once again, I must stress the fact that the key to recovery is stopping fin rot in its tracks before the bacteria penetrates the tissue and the body of the seahorse becomes infected." (Giwojna, Step-By-Step Book about Seahorses, pp. 57-58)
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Nowadays, of course, we have much better treatments at were available in Mildred Bellomy days, and I would not bother with copper sulfate or the topical treatment she mentioned at all. Rather, I would recommend treating the affected seahorses with antibiotic therapy in your hospital tank or makeshift treatment bucket. For example, sulfa antibiotics that are combined with trimethoprim are often very effective in treating fin rot.

Either TMP-sulfa or 4 Sulfa TMP would therefore be a very good choice for treating fin rot:

Trimethoprim and Sulfathiazole Sodium (TMP-Sulfa)

A potent combination of medications that’s effective in treating both gram-positive and gram-negative bacterial infections. It exerts its anti-microbial effect by blocking two consecutive steps in the biosynthesis of nucleic acids and proteins essential to many bacteria, making it very difficult for bacteria to develop resistance to the medications. TMP-Sulfa may be combined with other sulfa compounds to further increase its efficacy and decrease the chance of resistant strains developing. TMP-Sulfa will knock your biofilter for a loop, so be sure to use it in the hospital tank only.

These forms of sulfa can be obtained via National Fish Pharmaceuticals without a prescription, as can formalin. Just copy the following URL, paste it in your web browser, and press the "Enter" key, and it will take you to the proper website:

Okay, Lee – that’s the quick rundown on fin rot in seahorses.

In the meantime, double check the specific gravity in your aquarium since fin rot is sometimes associated with high salinity.

Before you begin treating with the TMP-Sulfa, however, I suggest administering a formalin bath, as explained below:

<open quote>
Formalin Bath

Formalin (HCHO) is basically a 37% solution of formaldehyde and water. It is a potent external fungicide, external protozoacide, and antiparasitic, and is thus an effective medication for eradicating external parasites, treating fungal lesions, and reducing the swelling from such infections. It is a wonder drug for treating cases of Popeye caused by trematodes, and also eradicates external nematodes.

Formalin can also be useful in treating fish with the following clinical symptoms:

Increased respiration; loss of normal body color; presence of discrete white spots (freshwater or saltwater "ich"); white areas on the body with circumscribed, reddish perimeter (Epistylis and/or bacterial infection); scratching on tank bottom or objects, lethargy, white cottony tufts or strands on body (fungus); dust-like, "peppered", yellowish spots on body surface (Oodinium); whitish skin slime or filmy body covering or patches (columnaris disease); disintegrating fins or fin edges (fin rot); mouth "fungus" (bacterial infection); pustules, furuncules or ulcers.

If any of the above symptoms are similar to the problems you’ve noticed with your seahorse upon close inspection, then administering formalin baths to the affected pony may be helpful.

In my experience, provided it is administered properly, seahorses tolerate treatment with formalin very well at therapeutic dosages. For a long term bath the correct dose is 15 to 25 mg/L. [Note: 25 mg/L equals 1 ml (cc) of 37% formalin per 10 gallons of water.] This is done every other day for 3 treatments.

For a short term bath (dip) the correct dose is 250 mg/L. This would equal 1 ml (cc) of 37% formalin per 1 gallon of water. This should be for about 45 minutes to 1 hour. In my opinion, formalin is a safe, effective treatment for parasitic infections in seahorses providing you don’t exceed these dosages and observe the following precautions for administering the medication properly:

Many commercial formalin products are readily available to hobbyists, such as Kordon’s Formalin 3, Formalin-F sold by Natchez Animal Supply, and Paracide-F, sold by Argent go to top Chemical Laboratories. Or whatever brand of formalin is available at your fish store should work fine, Claire. In your case, I am recommending a short-term bath in formalin as described below, after which you can release the seahorse in your hospital tank for further treatment:

A formalin bath simply involves immersing the seahorse in a container of saltwater which contains the proper dosage of formalin for a period of 30-60 minutes before transferring it to your hospital tank. Include a hitching post of some sort in the container and follow these instructions: place the fish in a three-gallon bucket or a similar clean, inert container containing precisely one gallon of siphoned, aerated tank water. Medicate the bucket of water with with the appropriate amount of formalin for a concentrated bath according to the directions on the label. Place an airstone in the bucket and leave the fish in the bath for 30 minutes. If at any time the fish becomes listless, exhausted or loses its balance, immediately place the fish in clean, untreated water in your hospital tank.

I want you to be aware of these precautions when administering the formalin bath:
Formalin has limited shelf life and degrades to the highly toxic substance paraformaldehyde (identified as a white precipitate on the bottom of the solution); avoid using any formalin product which has such a precipitate at the bottom of the bottle.
Formalin basically consumes oxygen so vigorous aeration must be provided during treatment.
Time the bath closely and never exceed one hour of chemical exposure at this concentration.
Observe the seahorse closely during the bath at all times, and it show signs of distress before the allotted time has elapsed, remove it from the treatment immediately.

If you can obtain Formalin 3 from Kordon at your LFS, Lee, these are the instructions you should follow for your formalin dip:

(a) To a clean, non-metallic container (i.e., a plastic bucket), add one or more gallons of fresh tap water treated with Kordon’s AmQuel . For marine fish use freshly prepared saltwater adjusted to the same specific gravity (or salinity) as in the original tank. Make sure the temperature in the container is identical to that in the aquarium
(b) Add 1 teaspoons of Formalin•3. This produces a concentration of 100 ppm. formaldehyde.
(c) Agitate the solution with an airstone and adjust for a moderately strong flow of air.
(d) Remove the fishes to be treated and deposit them in the container for a treatment period of not more than 50 minutes. Immediately after the treatment period, or if signs of distress are noted, remove the fishes to a previously prepared recovery tank. The fishes may be returned to their original tank, but the presence of the original disease-causing agents in the tank water may result in a reoccurrence of the disease condition.
(e) Observe recovering fishes. Make sure that tankmates do not molest them during recovery.
(f) Repeat treatment as needed, every week. Each treatment is very stressful to the treated fishes. Do not reuse the dip solution.

For additional information on treating fishes with Formalin 3 by Kordon, see the following web page:

Click here: KPD-54 Formalin-3

If you get another brand of formalin, just follow the instructions that it comes with for a concentrated bath or dip (not prolonged immersion or a long-term bath) or use the following directions:

FORMALIN Short-Term BATH Dosage and Preparation Instructions
Active Ingredient: 37% Formaldehyde
Indication: external parasites
Brand Names: Formalin, Formalin-MS
Notes: 1. Do NOT use Formalin that has a white residue at the bottom of the bottle. White residue indicates the presence of Paraformaldehyde which is very toxic. 2. "Formalin 3" by Kordon contains only 3% Formaldehyde. Dosing instructions will need to be modified if using this product.
• Fill a small tank with aged, aerated, dechlorinated marine water. Match the pH, temperature, and salinity to that of the tank the Seahorse is currently in.
• Add an artifical hitch and 1–2 vigorously bubbling airlines. Formalin reduces dissolved O2 so heavy aeration is required.
• Add 1ml/cc of Formalin per one gallon (3.8 liters) of tank water. Allow several minutes for the Formalin to disperse.
• Place the Seahorse into the dip water for 45–60 minutes unless it is showing signs of an adverse reaction. If the Seahorse cannot tolerate the Formalin dip, immediately move it back to the hospital tank.
• Observe the Seahorse for 24hrs for signs of improvement.

If you have to order the TMP-Sulfa and/or formalin from an online source such as National Fish Pharmaceuticals, Lee, then I would recommend placing your order, obtaining some Instant Ocean Lifeguard locally right away, and treating the seahorse in a hospital tank using the lifeguard immediately.

Instant Ocean Lifeguard is easy to use, inexpensive, and often available at local fish stores, including Petco and Petsmart retail stores so it is easy to obtain, allowing you to begin treatment promptly, which is very important for obtaining good results. The product may have a variety of different names depending on where you purchase it, including Instant Ocean Lifeguard, Instant Ocean Lifeguard Saltwater, or Instant Ocean Lifeguard All-in-One Marine Remedy. (There is also a Lifeguard medication available for freshwater, so be sure you get the Lifeguard for treating marine fishes, Lee.)

Here is some more information explaining the type of problems Instant Ocean Lifeguard is often effective in treating and how to use the medication:

Instant Ocean Lifeguard

Instant Ocean Lifeguard Saltwater tablets with HaloShield® attack a broad range of external fish diseases in saltwater aquariums including bacterial, fungal, viral, and parasitic. It’s HaloShield®, a revolutionary non-antibiotic agent, that makes LIFEGUARD pre-measured tablets so tough on harmful disease-causing microorganisms.

It is made by Instant Ocean, it is specifically for marine use and treats the following: ick, oodinium, fungus,milky or shedding slime,bacterial gill disease, mouth and fin rot, clamped or torn fins, and ulcers.

Safeguard tanks with LIFEGUARD! One tablet treats 10 gallons of water, recommended treatment is for five days.

Keep your aquatic pets healthy and fit with Instant Ocean LIFEGUARD All-In-One Marine Remedy. This therapeutic treatment is ideal for marine fish and treats clinical signs of diseases in its earliest stages. HaloShield® eliminates disease-causing microorganisms, and each tablet is premeasured for precise dosage and dissolves easily in water. Instant Ocean Lifeguard Saltwater is effective against marine Ick & Oodinium.

Ideal for use with marine fish
Treats a range of diseases, including bacterial, fungal, viral and parasitic conditions
HaloShield destroys disease-causing microorganisms
Effective against marine ick and oodinium
Tablets are premeasured and dissolve easily
Add 1 tablet per day to each 10 gal. of water
Made in the USA

Active ingredients: 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone.

Before treatment, remove filter carbon and turn off UV sterilizer. Add one tablet per day to each 10 US gallons of aquarium water using the enclosed treatment apparatus. Use treatment for 5 consecutive days, at 24-hour intervals. For best results, after 5-day treatment is complete, wait 24 hours (day 6), then return activated carbon and turn on UV sterilizer. Perform a 25% water change using a dechlorinator and a bacteria-enzyme to condition aquarium water. To treat smaller aquariums, break tablet along score lines. Each 1/4 tablet treats 2-1/2 US gallons.

Keep out of reach of children. For aquarium use only. Not for use on food fish. Not suitable for invertebrates or newly set up aquariums. Some macroalgae may show sensitivity. Use only as directed. Do not overdose. If overdose occurs, add carbon or dechlorinator as directed for immediate neutralization.

Available in a 16 pack

Okay, Lee, that’s the rundown on the Instant Ocean Lifeguard, which is what I would recommend that you try at this point if you do not have formalin or TMP-Sulfa on hand right now. In order to use the Instant Ocean Lifeguard, you would need to treat your seahorse in a quarantine tank or hospital tank, perform a 100% water change each day to maintain optimum water quality, and then re-dose with the medication according to the instructions above each day for five consecutive days. 24 hours after the fifth treatment (i.e., on the sixth day of treatment), you can return the seahorse’s) to the main tank.

If you don’t have a hospital tank or quarantine tank up and running at this time, Lee, you will need to set one up. This is what I normally advise home hobbyists regarding a suitable hospital tank, Lee:

<Open quote>
Basic Hospital Tank set up

Live sand and live rock are not necessary in a hospital tank. A bare-bottomed aquarium with plenty of hitching posts will suffice for a hospital ward or Quarantine Tank (QT). Ideally, the hospital tank should have one or more foam filters for biofiltration along with a small external filter, which can easily be removed from the tank during treatment but which can hold activated carbon or polyfilter pads when it’s time to pull the meds out. It’s important for the hospital ward to include enough hitching posts so that the seahorse won’t feel vulnerable or exposed during treatment. Aquarium safe, inert plastic plants or homemade hitching posts fashioned from polypropylene rope or twine that has been unraveled and anchored at one end are excellent for a hospital tank. No aquarium reflector is necessary. Ambient room light will suffice. (Bright lights can breakdown and inactivate certain medications and seahorses are more comfortable and feel more secure under relatively dim lighting.)

So just a bare tank with hitching posts is all you need for your hospital ward. No heater. No reflector. No lights. No substrate. You can even do without the sponge filters or external filter in your case, just adding a couple of airstones to provide surface agitation and oxygenation. That’s it.

In a pinch, a clean 5-gallon plastic bucket (new and unused, NOT an old scrub bucket!) can serve as a makeshift hospital tank. It should be aerated and equipped with hitching posts and perhaps a heater, but nothing else. This makes a useful substitute when the Quarantine Tank is occupied or in use and a seahorse needs treatment.

Stay on top of water quality in the hospital tank/bucket with water changes as often as needed during treatment, and and when you are treating the occupants for a health problem, re-dose with the medication(s) according to directions after each water change.
<close quote>

As you can see, Lee, hospital tank is pretty easy to set up because it’s not intended to house the seahorses long-term, only while they undergo a treatment regimen that usually lasts 5-14 days.

For filtration, I keep things really simple in a hospital tank, using only foolproof air-operated sponge filters for my dwarf seahorses. Avoid sponge filters with weighted bottoms or other metal components, however, since they will rust when exposed to saltwater. Sooner or later this will cause problems in a marine aquarium (sooner in the small setups that are most suitable for H. zosterae). Select a sponge filter that has no metal parts and is safe for use in saltwater. The proper units will have suction cups to anchor them in place rather than a weighted bottom.

The sponge filters I find that work well are the Oxygen Plus Bio-Filters (models 2, 3, 4, or 5) or the Tetra Brilliant foam filters. They have no metal components, making them completely safe for use in saltwater, and just one of these foam filters will do the job on a tank of 5 gallons or less. They do not have a weighted bottom but are equipped with suction cups instead. Two of the smaller models can be used on larger 25-gallon tank like yours, Lee, but one of the larger models, like the one at the link below, would be sufficient for your 10-gallon aquarium:

Click here: Foam Aquarium Filters: Oxygen Plus Bio-Filter 2

Avoid the Oxygen Plus Bio-filter 6, 11, and the Multi sponge, which all have a weighted bottom (metal), that rusts when exposed to saltwater. If you want more filtration, you’re better off going with two of the smaller suction cup sponge filters rather than any of the models with weighted bottoms.

All you need to operate sponge or foam filters is an inexpensive, diaphragm-operated air pump (whatever is available at a reasonable price from your LFS will do just fine), a length of airline tubing to connect the air pump to the foam filter(s), and a set of air valves (gang valves) to regulate the air flow to the filters. That’s all — nothing to it! The inexpensive Apollo 5 air pumps work great for sponge filters, but whatever air pump you have on hand should certainly do the job.

Cleaning the foam filters is a snap. Simply immerse them in a bucket of saltwater and gently squeeze out the sponge until it’s clean and releases no more sediment or debris. Run a bottlebrush through the inside of the tube, wipe off the outside of the tube, and you’re done. The filter is ready to go back in the aquarium with no impairment at all of the biofiltration. Takes only a couple minutes.

Okay, Lee, those are my thoughts regarding setting up a hospital tank.

Best of luck obtaining the medications you need to treat this problem and restoring your seahorse to good health.

Pete Giwojna, Ocean Rider Tech Support

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